Arteriovenous fistula hemodialysis access

Special attention in such patients focuses on the presence and function of preexisting arteriovenous fistulae, hemodialysis central venous catheters, or access for peritoneal dialysis. Arms with vascular accesses are kept free from blood pressure cuffs, pulse oximeters, tourniquets and peripheral venous cannulae. 

Due to fewer complication and longer survival rates, the native arteriovenous fistula is the preferred access for hemodialysis. Venous catheters are plagued by complications such as infection and thrombosis and often deliver relatively poor blood flow rates. 

Catheters are placed when there is a clinical need for repeated sampling, injection, or vascular access, usually on a temporary basis. In kidney failure, catheters allow emergent blood access for hemodialysis and hemofiltration (Canaud, 2000), and provide temporary access as more permanent sites such as arteriovenous fistulas or grafts mature rerotola, 2000). Placement of a catheter or access port is routine for the administration of chemotherapeutic agents and intravenous nutritional supplements. Catheters are often placed when frequent, repeated doses of medication are to be injected. 

Holley [21] conducted a study of adverse events and medical errors in four hemodialysis units. Incident data are based on reports by the units clinical directors. Among nearly 65,000 dialysis treatments, 88 errors occurred (1 event/ 733 treatments). Infiltration of the hemodialysis access, clotting of the dialysis circuit and omitted medications were common problems. In a surveillance study of dialysis patients in Gran Canaria (Spain), the incidence rate of adverse events was 8.6/100 patient-months [22]. The rate was higher among patients with arteriovenous fistula (9.1/100 patient-months) compared to patients with permanent catheter (2.9/100 patient-months). The preventability of the events is unknown. 

It is important to identify patients who may eventually require renal replacement therapy since adequate preparation can decrease morbidity and perhaps mortality. Early identification enables dialysis to be initiated at the optimal time with a functioning chronic access. The placement and adequate maturation of arteriovenous fistula (AVF) before the initiation of hemodialysis therapy requires timely patient education and counselling, selection of the preferred renal replacement modality, selection of an access type and location, and creation of the access at least several weeks to months in advance of its expected need. An early constructed AV fistula could also have a beneficial effect on the rapidity of worsening kidney failure. Reasons for this could be increased heart preload and consequently increased afterload or decreased peripheral resistance with increased renal perfusion. A simpler reason could be that patients after AV fistula construction become aware that situation is serious and they start to follow the therapy more accurately [11]. 

Vaes RH, Tordoir JH, Scheltinga MR Systemic effects of a high-flow arteriovenous fistula for hemodialysis. J Vase Access 2014 15 163-168. 

Ilhan G, Esi E, Bozok S, Yurekli I, Ozpak B, Ozelci A, Destan B, Gurbuz A The clinical utility of vascular mapping with Doppler ultrasound prior to arteriovenous fistula construction for hemodialysis access. J Vase Access 2013 14 83-88. 

Dialysis vascular access is currently the lifeline for hemodialysis patients. Unfortunately, due to the many complications associated with dialysis vascular access, it is also the Achilles heel of hemodialysis. A relatively ignored aspect of dialysis vascular access pertains to patient safety. The first part of this chapter will describe patient safety issues in the traditional context of arteriovenous fistulas (AVFs), arteriovenous grafts (AVGs) and tunneled central venous catheter (tCVC). In the second half of this chapter, however, we will make the case that a nontraditional approach which emphasizes (a) individualization of care, and (b) patient preferences and patient involvement maybe our best opportunity to improve patient safety in hemodialysis patients. 

Hemodialysis (HD) catheter-associated bloodstream infections (BSls) are a type of CLABSI due to a central venous catheter (CVC) specifically designed for HD. In 2002, it was estimated that 50,000 CLABSIs occur in dialysis patients in the US annually. A more recent surveillance study found the rate of access-related BSIs to be 0.73 events per 100 patient-months [5]. Aside from catheters, patients in need of renal replacement therapy should eventually use arteriovenous fistula (AVF) or arteriovenous grafts (AVG) for HD, or alternatively, may receive peritoneal dialysis. All renal replacement therapies are associated with a risk of infection however, this risk varies with the method selected. Data from a CDC surveillance program display nicely how the type of access influences the BSI rate per 100 patient-months 0.5 (for AVFs), 0.9 (AVG), 4.2 (permanent CVCs), and an impressive 27.1 for temporary CVCs [6]. Another, more practi-... 

Saran R, Elder SJ, Goodkin DA, Akiba T, Ethier J, Rayner HC, Saito A, Young EW, Gillespie BW, Merion RM, Pisoni RL Enhanced training in vascular access creation predicts arteriovenous fistula placement and patency in hemodialysis patients results from the Dialysis Outcomes and Practice Patterns Study. Ann Surg 2008 247 885-891. 

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